java - Android Firebase 数据库检查用户是否属于特定组

Question

我有 5 种不同的用户类型，我想检查用户是否属于 4 种特殊用户类型之一，并据此更改菜单 ui。这是我自己发现的，但不起作用。

mDatabase.child("staff").orderByChild(mAuth.getUid()).equalTo("true").addValueEventListener(new ValueEventListener() {
            @Override
            public void onDataChange(@NonNull DataSnapshot dataSnapshot) {
                String staffType = dataSnapshot.getKey();
                if (staffType == "servers"){
                    mTitles = new ArrayList<>(Arrays.asList(getResources().getStringArray(R.array.menuUser)));
                }
            }

我的 Firebase 数据库

Answer 1

更改此:

if (staffType == "servers"){
mTitles = new ArrayList<>(Arrays.asList(getResources().getStringArray(R.array.menuUser)));
}

进入此:

if (staffType.equals("servers")){
mTitles = new ArrayList<>(Arrays.asList(getResources().getStringArray(R.array.menuUser)));
}

来自文档:

public boolean equals(Object anObject)

Compares this string to the specified object. The result is true if and only if the argument is not null and is a String object that represents the same sequence of characters as this object.

https://docs.oracle.com/javase/7/docs/api/java/lang/String.html#equals(java.lang.Object)